It is perhaps not so baffling that we have the ability to develop,
refine, and manifest a creative idea, once it has been conceived. But what
sort of a system could spawn the initial seed of creativity from which
an idea grows? This paper looks at how the mind is structured in such a
way that we can experience a glimmer of insight or inkling of artistic
inspiration.

1. MEMORY IS DISTRIBUTED BUT CONSTRAINED

Before we can explore how the contents of the mind are harnessed in
a unique and innovative way, it is necessary to look briefly at how experiences
are encoded in memory, and how they participate in subsequent experiences
through contextual reminding events.

If the mind stored each experience in just one memory location as a
computer does (Figure 1a), then in order for one experience to evoke a
reminding of a previous experience, it would have to be identical
to that previous experience. And since the space of possible experiences
is so vast that no two ever are exactly identical, this kind of
organization would be pretty useless. On the other hand, if any experience
could activate any memory location (Figure 1b), the memory would be subject
to crosstalk, a phenomenon wherein nonorthogonal patterns interfere. For
the mind to be capable of evolving a stream of coherent yet potentially
creative thought, the degree to which an experiences is distributed
must lie between these extremes; that is, the size of the sphere of activated
memory locations must fall within an intermediate range. A given instant
of experience activates not just one location in memory, nor does
it activate every location to an equal degree, but activation is
distributed across many memory locations, with degree of activation decreasing
with distance from the most activated one, which we call k (Figure
1c). The further a concept is from k, the less activation it not
only receives from the current stimulus but in turn contributes
to the next instant of experience, and the more likely its contribution
is cancelled out by that of other simultaneously activated locations. A
wide activation function means that locations relatively far from k
still get activated; in other words, neurons have a lower activation threshold,
so more fire in response to a given stimulus.

Figure 1. (a) A one-to-one correspondence
between input and memory, as in a computer. (b) A distributed memory,
as in some neural networks. (c) A constrained distributed memory,
as in neural networks that use a radial basis function for the activation
function. This is closest to how human memory works.

2. MEMORY IS CONTENT ADDRESSABLE

There is a systematic relationship between the content of an
experience (not just as the subject matter, but the qualitative feel of
it) and the memory locations where it gets stored (and from which material
for the next instant of experience is evoked). In a computer, this kind
of one-to-one correspondence is accomplished by assigning each possible
input a unique address in memory. Retrieval is thus simply a matter of
looking at the address in the address register and fetching the item at
the specified location. The distributed nature of human memory prohibits
this, but content addressability is still achievable as follows. The pattern
of features (or phase relations) that constitutes a given experience induces
a chain reaction wherein some neurons are inhibited and others excited.
The address of a neuron is thus the pattern of excitatory and inhibitory
synapses that make it fire. Since correlated qualia patterns get stored
in overlapping locations, what emerges is that the system appears to retrieve
experiences that are similar, or concepts that are relevant, to the current
experience. As a result, the entire memory does not have to be searched
in order for, for example, one painting to remind you of another.

3. A DISTRIBUTED, CONTENT ADDRESSABLE MEMORY CAN BE CREATIVE

A distributed, content addressable memory has advantages and disadvantages.
Since stored items are 'smooshed' together in overlapping locations, at
a high level of resolution, an item is never retrieved in exactly
the form it was stored. Your new experience of it is reinterpreted in the
context of similar experiences, and colored by events that have taken place
since the last time you thought of it, as well as current stimuli, goals,
and desires. Thus it is more accurate to think of the evoking process as
reconstruction rather than retrieval.

Although this 'smooshing'/reconstruction is a source of inaccuracy,
it enables the emergence of abstractions-concepts such as 'depth'
with fewer dimensions than any of their instances. Abstractions unite stored
experiences into an interconnected mental model of reality, or (from a
first person standpoint) subjective worldview (Gabora 1998). The more abstract
the concept, the greater the number of others potentially evoked by it.
For instance, your concept of 'depth' is deeply woven throughout the matrix
of concepts that constitute your worldview. It is latent in experiences
as varied as 'deep swimming pool', 'deep-fried zucchini', and 'deeply moving
book'; it derives its existence from these instances. The identification
of an abstraction is a creative act. Often, however, when we think of creativity,
we think of the invention of artifacts that merge lower-dimensional entities
into something more complex than its constituents; for example,
a dance is more than its steps. The 'smooshed' nature of human memory is
the wellspring of both sorts of creativity. The more interwoven
the mind is with abstractions, the more different ways of funneling an
experience through the conceptual network, abstracting something new out
of it, and manifesting the essence, or feel of it, through the constraints
of an artistic medium (Gabora 2000).

4. THE CREATIVE INKLING

The current array of sensory stimuli can be viewed as a perturbation
that impinges on the current spatio-temporal pattern of activated memory
locations to create a new constellation of activated locations.
You could say the perturbation collapses the conceptual network
into a phenomenally manifested state; it reveals one 'slice' through the
distribution of possibilities that was inherent in the conceptual network
(Aerts & Gabora 1999). In a sense, the perturbation tests the integrity
of a certain portion of the worldview, the size of the portion tested depending
on the activation function. At the risk of mixing metaphors, you could
say it's like throwing a ball against a wall and observing how it responds.
The more flexible the material the ball is made of, the more it 'gives'
when it makes contact. Similarly, the wider the activation function, the
greater the portion of the worldview that makes contact with the world
at that instant. Much as irregularities in the bounced ball cause its path
to deflect, constrictions (repressed memories) or gaps (inconsistencies)
in the 'collapsed' portion of the worldview may cause tension and thereby
indicate a need for creative release, revision, or reconstruction. (Of
course, so long as the ball doesn't completely deflate and slide down the
wall, you're doing fine. :-)

An inkling, then, is a collapse on an association or relationship
amongst memories or concepts that, although their distribution regions
overlap, were stored there at different times, and have never before been
simultaneously perturbed, and evoked in the same collapse (Figure 2). Though
it is a reconstructed blend, something never actually experienced,
it can still be said to have been evoked from memory. It's like getting
a 'bite' on many fishing rods at once, and when you reel them in you get
a fish that is a mixture of the characteristics of the various fish that
bit.

Figure 1. Schematic diagram of stimulus
activating two dimensions of memory. Each vertex represents a possible
memory location, and black dots represent actual locations. If many
memories are stored in locations near k, they blend to generate
the next experience.

5. MENTAL STATES CONDUCIVE TO CREATIVITY

If the activation function is large, a greater diversity of memory locations
participate in the encoding of an instant of experience and release of
'ingredients' for the next instant. The more locations activated, the more
they in turn activate, and so on; thus streams of thought tend to
last longer. However, consecutive instants are less correlated because
a concept from the periphery of the sphere of activated locations can pull
the content of the next instant of experience far from its predecessor.
New stimuli less readily command attention because they must compete
with what has been set in motion by previous stimuli. If, however, something
does manage to attract attention, it can get thoroughly assimilated
into the matrix of abstractions, and thereby become increasingly decoupled
from the stimulus that initially triggered it.

In the long run, since the relationship between one thought and the
next could be so remote that a stream of thought lacks continuity, a large
activation function would be untenable. However, in the short run, since
there is a high probability of 'catching' new combinations of memories
or concepts, it is conducive to creativity. The more features of the environment
one attends or is sensitive to, the more memory locations potentially involved
in its storage; thus, a large activation function may manifest as a state
of defocused attention or heightened sensitivity. There is in fact experimental
evidence that both defocused attention (Dewing & Battye 1971; Dykes
& McGhie 1976; Mendelsohn 1976), and high sensitivity (Martindale &
Armstrong 1974; Martindale 1977), including sensitivity to subliminal impressions
(Smith & Van de Meer 1994) are associated with creativity.

One measure of creativity is the steepness of an individual's associative
hierarchies (Martindale 1999; Mednick 1962). This is measured experimentally
by comparing the number of words that individual generates in response
to stimulus words on a word association test. Those who generate only a
few words in response to the stimulus (e.g. 'chair' in response to 'table')
have a steep associative hierarchy. Those who, after running out
of the usual responses go on to generate unusual ones (e.g. 'elbow' in
response to 'table') have a flat associative hierarchy. This is
what one would expect with a wide activation function.

6. THE CREATIVE BEING AS CONDUIT

To make this more concrete let us take an example. Sometimes freestyle
dancers find themselves 'doing moves', but unable to lose themselves to
the music. The dancing feels and looks planned, does not touch the heart.
Dance demands that the music be allowed to have its way with you, to forge
new channels of expression through the constraints of your body, to use
you to unearth something new. Perhaps this state, and its analog in other
creative endeavors, derives from a state of defocused attention-thus widened
activation function-such that whatever gets evoked, whether the
logic of the association is apparent or not, can surface to the next instant
of awareness.

Let us look at the effect an inkling has on the conceptual network or
worldview. The biological concepts of linkage equilibrium and disequilibrium
are useful for gaining perspective on what is happening here. The closer
together two genes are on a chromosome, the greater the degree to which
they are linked. Linkage equilibrium is defined as random
association amongst alleles of linked genes. Consider the following example:

A and a are equally common alleles of Gene 1.

B and b are equally common alleles of Gene 2.

Genes 1 and 2 are linked (nearby on same chromosome).

There are four possible combinations of genes 1 and 2:
AB, Ab, aB, and ab. If these occur with equal
frequency, the system is in a state of linkage equilibrium. If not, it
is in a state of linkage disequilibrium. Disequilibrium starts out
high, but tends to decrease over time because mutation and recombination
break down arbitrary associations between pairs of linked alleles. However,
at loci where this does not happen, one can infer that some combinations
are fitter, or more adapted to the constraints of the environment, than
others. Thus when disequilibrium does not go away, it reflects some structure,
regularity, or pattern in the world.

What does this have to do with creativity? Like genes, the features
of memories and concepts are connected through arbitrary associations as
well as meaningful ones. We often have difficulty applying an idea or problem-solving
technique to situations other than the one where it was originally encountered,
and conversely, exposure to one problem-solving technique interferes with
ability to solve a problem using another technique (Luchins 1942). This
phenomenon, referred to as mental set, plays a role in cultural evolution
analogous to that of linkage in biological evolution. To incorporate more
subtlety into the way we carve up reality, we must first melt away arbitrary
linkages amongst the discernable features of memories and concepts, thereby
increasing the degree of equilibrium. As we destroy patterns of association
that exist because of the historical contingencies of a particular domain,
we pave the way for the forging of associations that reflect genuine structure
in the world of human experience which may manifest in several or perhaps
all domains. This needn't be an intellectual process. For example,
one might have a sudden glimmer of insight into how the feeling
of a particularly emotional experience could be extricated from the specifics
of that experience, and re-manifest itself as, say, a piece of music.

ACKNOWLEDGEMENTS

I would like to acknowledge the support of the Center Leo Apostel and
Flanders AWI-grant Caw96/54a. And I guess I have to thank my cat Inkling
for inspiration.